Disposable blood pressure cuff

ABSTRACT

A one-piece, disposable blood pressure cuff comprising two layers of a flexibly pliable, elongated, thermoplastic polymer film peripherally bonded together to form an inflatable pocket therebetween, the outer film of said cuff being capable of withstanding a tensile force of 10 pounds per inch of width and capable of withstanding pressures of 300 mm. of Hg at inflation without elongating more than 20 percent. The inner film of said cuff must be capable of withstanding a tensile force of 5 pounds of force per inch of width and have an elongation of 20 percent or less when the cuff is inflated to a pressure of 300 mm. Hg. The inner elongated film layer is attached to a nontoxic, nonirritating substrate suitable for contact with human skin, said substrate having a compressibility of less than 3/16 inch. The cuff has means for the introduction and evacuation of air from the pocket, means to hold a blood pressure cuff transducer on said substrate and against the skin and means to attach the end of the cuff onto a portion of itself when overlapped and convolutely wrapped around an appendage, thus holding the cuff on during the measurement of a patient&#39;&#39;s blood pressure.

United States Patent 1 Weyer DISPOSABLE BLOOD PRESSURE CUFF [75]Inventor: James H. Weyer, Afton, Ohio [73] Assignee: Minnesota Miningand Manufacturing Co., St. Paul, Minn.

22 Filed: m.2,1971

21 Appl. No.: 203,995

Related US. Application Data [63] Continuation-impart of Ser. No.876,778, Nov. 14,

1969, abandoned.

[52] US. Cl 128/2.05 C [51] Int. Cl A6lb 5/02 [58] Field of Searchl28/2.05 A, 2.05 C,

128/205 0, 2.05 M, 2.05 P, 2.05 O, 2.05 R, ..l2/.Z -95 512.953. 22.105Z1 2 .2

[56] References Cited OTHER PUBLICATIONS Hammer et a1. IBM TechnicalDisclosure Bulletin, Vol. 8, No. 4, September, 1965, p. 593.

[ Nov. 20, 1973 [57 ABSTRACT A one-piece, disposable blood pressure cuffcomprising two layers of a flexibly pliable, elongated, thermoplasticpolymer film peripherally bonded together to form an inflatable pockettherebetween, the outer film of said cuff being capable of withstandinga tensile force of 10 pounds per inch of width and capable ofwithstanding pressures of 300 mm. of Hg at inflation without elongatingmore than 20 percent. The inner film of said cuff must be capable ofwithstanding a tensile force of 5 pounds of force per inch of width andhave an elongation ofgggergentgr less when the cuff is inflated to apressure of 300 mm. Hg. The inner elongated film layer is attached to anontoxic, nonirritating substrate suitable for contact with human skin,said substrate having a compressibility of. less than 3/16 inch. Thecuff has means for the introduction and evacuation of air from thepocket, means to hold a blood pressure cuff transducer on said substrateand against the skin and means to attach the end of the cuff onto aportion of itself when overlapped and convolutely wrapped around anappendage, thus holding the cuff on during the measurement of a patients blood pressure.

9 Claims, 8 Drawing Figures PAIENIEUnuvzo ms 3773; 036

sum 1 or 2 IN VENTOR. JAMES h. WEYZR FIG- 6 ATTORNEYS 1 DISPOSABLE BLOODPRESSURE CUFF BACKGROUND OF THE INVENTION This is a continuation-in-partof co-pending application Ser. No. 876,778, filed Nov. 14, 1969, nowabandoned.

The invention relates generally to a one-piece, disposable bloodpressure cuff for measuring blood pressure adapted to be convolutelywrapped around an appendage and which can be subsequently discarded.More particularly, the invention relates to a disposable blood pressurecuff made of two layers of a soft, pliable, thermoplastic polymer filmperiphery bonded together andproviding an inflatable bladder for all ora portion of the length thereof, the skin-contacting surface of the cuffbeing surfaced with a soft, porous, moisture vapor permeable material,such as a fine sponge, textile, nonwoven fabric, or the like.

The measurement of blood pressure with blood pressure cuffs consists oftightening the cuff about the upper arm and obtaining readings of thesystolic pressure, which is the greatest or peak pressure of the bloodin an artery during a heartbeat, and the diastolic pressure, which isthe pressure of the blood in an artery between heartbeats. The bloodpressure cuff has attached to it a device for measuring the pressure ofthe air in an inflatable bladder usually carried as a separate unitwithin the cuff. A stethoscope is used with the cuff to monitor thesounds the blood makes when passing through the constricted artery. Thestethoscope is generally used adjacent to the cuff on the arm and not atthe precise site of arterial constriction. The bladder is then slowlyreleased until the needle on the blood pres sure measuring device beginsto bounce indicating blood is beginning to pass through the constrictedartery at a certain pressure, which pressure is considered the systolicpressure. The diastolic pressure is much harder to determine but isgenerally considered to be about at that point where the needle ceasesthe bounce during reduction of the pressure.

A problem that exists with presently used blood pressure cuffs iscross-contamination between patients. Blood pressure cuffs generallycomprise a cloth-like cover into which-a rubber bladder is inserted. Asa physician normally takes numerous blood pressure readings during ashort period of time, the cover on the cuff is placed on the arm of manypatients without any interim sterilization procedures being used tominimize the possibility of passing contamination from patient topatient.

An example of presently used blood pressure cuffs is shown in U.S. Pat.No. 3,567,077, where two plies of woven nylon fabricate stitchedtogether to form a hollow body suitable for the insertion of a bladder.The insertablebladderwill havemeansfor inflation and deflation and whensaid bladder is inserted in the hollow body, theassembled partsforma'blood pressure cuff. it is also disclosed, but not asa preferredembodiment, that a hollow body-could be formed from thermoplastic films.Merely heat bonding two layers of plastic together, however, is notsufficient. The prior art does 'not disclose a range of criticalparameters for thermoplastic films necessary to form aone-piece,disposable blood pressure cuff, since the prior art cuffs are 'designedtobe used with an inflatable bladder and, consequently, thephysicalproperties of the films are of slight importance. Where a bloodpressure cuff is'formed as an integral unit, the film layers definingthe cuff must possess a certain strength to allowproper inflation of thecuff while maintaining conformability while in use.

A further problem is that during surgery and in intene sive care wards,it is often desirable to keep the blood pressure instruments on the armfor long periods of time so that blood pressure may be frequentlymeasured.

When the blood pressure cuff is left in place for extended periods oftime, it is desirable that a thin, vapor permeable layer integrallybonded to the blood pressure cuff be placed next to the patients skin.The presently used blood pressure cuffs are not satisfactory for thispurpose as they are relatively heavy and bulky, causing the patient toperspire with no escape for this moisture, which may cause severediscomfort. It is not sufficient merely to place a layer of softmaterial on that portion of the cuff which contacts the patients skin,the material should allow the passage of vapor, be lightweight, and nothave a large compressible thickness which would hamper the swift andaccurate measurement of the blood pressure. Where there is insufficientvapor transport, or the vapor-permeable layer is heavy, leaving theblood pressure cuff in place for extended periods, it will result indiscomfort to the patient. Conversely, if the vapor-permeable layer istoo thick, large amounts of air will be required to properly inflate theblood pressure cuff which causes an undesirable increase in timenecessary to take a blood pressure reading. I

The mere addition of open mesh fabrics as taught by Hammer, IBMTechnical Disclosure Bulletin V. 8,

No. 4, page 593, or foam as taught by U.S. Pat. No. 2,271,927 will notcure the weight and comfort deficiencies of the prior art cuffs sincenot all fabrics and foams are vapor permeable, light in weight, andsuitable for contact with a patients skin over extended periods.

Further, it would be desirable that each patient has his own personalcuff when in isolation or intensive care. To applicants knowledge, thereis no one-piece, lightweight, complete, disposable blood pressure cuffavailable at the present time fulfilling the requirements notedheretofore.

SUMMARY OF THE INVENTION According to the present invention, adisposable, one-piece blood pressure cuff is provided which islightweight and comfortable to the patient, is inexpensive, and can beefiiciently manufactured on high speed automatic equipment. The novelcufi virtually eliminates cross-contamination between or among patientsand, thus, is particularly suited for use in isolation. The one-piececuff is further suited for use in the operating room as it may be lefton'the patients arm for extended periods of time without being attachedto a stethoscope or a monitoring device until use is desired, at whichtime said devices may be conveniently attached.

The new one-piece, disposable cuff of the present invention generallycomprises an outer layer of an elongated, generally rectangular strip ofthermoplastic polymer film having a minimum tensil strength of 10poundsper inch of width, which can withstand inflation pressures of upto 300 mm. Hg. without elongating more than 20 percent or exceeding theelastic limit; a second inner, generally rectangular layer ofthermoplastic polymer film overlying at least a portion of said firstlayer, the second layer having a minimum tensile strength of pounds perinch of width and capable of withstanding inflation pressures of 300 mm.Hg without elongating more than 20 percent or exceeding the elasticlimit, the two layers being sealed together about a perimeter to provideat least one inflatable pocket between said first and second layers;connecting means projecting from said second layer for inflation of saidpocket; a third layer of a soft, porous, conformable, moisture vaporpermeable, hypoallergenic material surfacing the back of said secondlayer for contact with the skin, said layer having a compressibility offrom about 1/64 to about 3/16 of an inch, and means to hold anaudio-pickup transducer onto said third layer. Upon use, the inflatablepocket portion is placed on the appendage and the remainder of the cuffis convolutely wrapped around the appendage and itself to preventbursting of the bladder when inflated. A portion of the cuff has acoating of pressure-sensitive adhesive thereon to anchor it to thatportion of the cuff with which it comes in contact when the cuff iswrapped over itself.

The objects and features of the present invention will be more fullyunderstood with reference to the drawings wherein:

FIG. 1 is a view of the one-piece blood pressure cuff as it is usedwhile attached to monitoring devices;

FIG. 2 is a perspective view of the outer surface on the cuff;

FIG. 3 is a cross section of the cuff;

FIG. 4 is a view of a modified cuff which has a reinforced surface;

FIG. 5 is a longitudinal cross section of the cuff of FIG. 4;

FIG. 6 is a transverse cross section of the cuff of FIG.

FIG. 7 is a graph showing tensile strength per inch of width incomparison to a certain film thickness for polyethylene; and

FIG. 8 is a graph showing stiffness versus film thickness forpolyethylene.

With reference to the drawings, FIG. 1 is an illustration of a bloodpressure cuff 10 made in accordance with the invention, wrapped aroundthe arm of a subject and having attached thereto a stethoscopeaudiopickup l2, and an inflating means 14 equipped with apressure-responsive gauge 22.

The construction of the cuff is best illustrated in FIGS. 2 and 3, thecuff comprising top and bottom layers 28 and 29 respectively of aflexible, nonporous, thermoplastic, polymeric film, such as polyethyleneor other plastic. These layers are sealed to one another about theirperiphery of the cuff as at 32, and are further heat sealed to oneanother at spaced intervals 33 along the length of the cuff, thusforming three pockets having sealing perimeters at 33 and 32. A soft,non toxic, nonirritating, porous, moisture vapor permeable substrate 36is attached to one layer 29 along about two-thirds of its length. Thissoft area contacts the skin during use allowing the cuff to be quitecomfortable while on the patients arm and allows the evaporation ofmoisture vapor from the skin. A portion of the cuff on the end whereinthe nonirritating substrate 36 is attached thereto forms a bladder orpocket 31 between the inner layer 29 and the outer layer 28. An air stem14 is attached near the end of the section forming the bladder to allowthe passage of air in and out of the bladder 31. Air is inserted intothe bladder by means of a pressure bulb 24 and tube 20 attached to thestem 14 and, upon release of the air pressure, a reading is taken on areadout dial 22 as illustrated in FIG. 1.

Although these pockets are illustrated between the film layers, eachpocket sealed around its perimeter, only one functions as the bladderdepending upon where the air stem is attached. The three pockets areformed only because it is easier to manufacture the cuff using twopieces of film of similar size to form the bladder 31 and the remainderof the cuff rather than forming a bladder and thereafter attaching athicker single piece of film thereto to form the remainder of the cuff.Similarly, a single piece of film folded centrally and sealed at itsedges will work satisfactorily, although two separate pieces of film arepreferred for manufacturing purposes.

The soft, conformable layer 36 has two slits (not shown) insertedtherein which hold an audio-pickup transducer 12 which in turn isconnected by means of a tube 16 to a stethoscope headset 18. On the sideopposite the soft layer 36, a small area of a pressuresensitive adhesive30 is attached to the central third of the cuff which serves to anchorthe cuff when convolutely wrapped over itself around an appendage and,thus aids in holding the cuff securely on the appendage.

The materials forming the cuff must be pliable enough so that the wallsof the bladder can comply to the introduction of air therein, but strongenough so that the walls will not burst. The outer film 28,- in order toperform adequately, must withstand a tensile force of 10 pounds per inchof width without exceeding the elastic limit of the film and withoutelongating more than 20 percent in order to withstand inflationpressures of 300 mm. of Hg when wrapped around an adult arm. Tensileforce as used herein is not to be confused with tensile strength. Whiletensile strength is constant with a given material, the tensile force isthe force required to exceed the elastic limit of a material at acertain thickness. In order to conform to the appendage around which thecuff is wrapped, the stiffness of the outer layer must not exceed 250mm. when using ASTM Federal Test Method Standard No. 191, Method 5204,entitled Stiffness of Cloth, Directional Self-weighted CanteleverMethod. This test comprises placing a speciman about 1.25 inches wideand about 6 to 12 inches in length between two cylinders in a devicewhich rotates the plane defined by the axes of said cylinders. Themeasure of directional flexstiffness shall be the length of the specimanremaining above the nip of the rollers which, when the test instrumentis rotated clockwise and counterclockwise through 2, just falls to theleft and right of the line perpendicular to the nip of the rolls. Amaterial which has a stiffness value in the range of approximately50-250 mm.- will conform readily to an appendage, and therefore, willproduce a blood pressure cuff which gives acceptable blood pressurereadings. Films having a Rockwell hardness greater than M are toobrittle to be used as the outer film of the cuffs, said films being toohard to be wrapped effectively about and conform to an appendage.

The inner film 29 of a blood pressure cuff can have a lower tensilestrength than the outer wrap since the appendage provides partialsupport for the inner film. For the inner film,-a tensile force of 5pounds per inch of width without exceeding the elastic limit and withoutelongating more than 20 percent is sufficient to form an acceptableblood pressure cuff which will withstand inflation to 300 mm. Hg.Stiffness of the inner film should not be greater than 125 mm.whenrneasured using ASTM Standard No. 191 mentioned hereinbefore inorder to assure proper, conformability." A Rockwell hardness of lessthan M120 is necessary to insure comfort and conformability of the cuff.Outer and inner films which have tensile force per inch of width lowerthan and 5 pounds respectively will result in blood pressure cuffs whichburst when inflated or which: will expand freely thrreby preventing asufficient pressure build up to construct an artery to make a pressurereading possible.

The film material should further be nonpermeable to air and heatsensitive so that it may be heat sealed, or in the alternative it shouldbe receptive to an adhesive or other means of sealing. Examplesofrnaterial's' capable of fulfilling the abovementioned requirementsarevinyls, nylon, polypropylene, and other pliable', thermoplasticpolymers.

The nontoxic, noni'rritating surface 36 which contacts theskinisattached to: the bladder 31 and any other portion ofthe film whichcontacts the skin. in the drawings, this material covers. abouttwo-thirds of the cuff, but may cover the entire cuff or any portionthereof. Fabrics such: as nonwoven webs are preferred, but any materialwhich isconformabl'e and noni'rritating to-fthe skin may be used,suchnas cloth, paper, sponge, p reticulated foam, or other porousmaterials. Whichever ,material' is used to form the non-irritatingsurface 36, the' noni rritating layer must have a maximum compressibility approachingfl to' lessthan. 5/1 6 of aninch.Noni-rritating layers with compressibility in excess of ill-1 6 of'aninch requirev inordinate amounts of air-to properly inflate the cuff to300 mm. of Hg pressure with a:. consequential undesirable increase inthe: amount of time required to take a blood pressure reading. When aflexible, open-celled foam is used as the nontoxic, nonirritating:surface, foams with a density of under 10 pounds per cubic feet arerequired since foams of greater density; result in a blood pressure cuffwhich is heavy and uncomfortable.

As noted previously, this material preferably has two slits therein to.-hold the audio-pickup: transducer 1'2 from a stethoscope when the cuffis placed-on 'the am, but such slits are not necessary where an ordinarystethoscope is merely placed under or near the cuff. The use of a pickuptransducer, however, has proved to be more reliable and convenient whenlistening to the heartbeats;

An air stem 14 or tube is permanently fixed in the bladder 31 so thatair may be introduced into the bladder and later released. The stem 14may be any type of hollow device, preferably plastic or metal, that issuitablystrong to be pushed through the film 28-forming the bladderallowing an impermeable friction fit to be" formed: between: the stemand the adjacent film and preferably capable of being tilted orotherwise brought out to the side of the cuff. In the case ofpolyethylene film, the film extrud'es over and around the" insertedstern sealing any spaces formed therebetween. The stem should also beadapted to receive the tubing which connects it tothe pressure bulb'2'4.

An adhesive 30is attached centrallyto the outersurface of the cuff sothat when the cuff is convolutely wrapped around itself, the end of thecuff opposite the bladder comes to rest upon the adhesive and adheresthereto, thus, holding the wrapped cuff together and on the appendage. Adouble-coated, pressure-sensitive adhesive tapeis satisfactory for mostapplicationsrAny fastenenhowever, which'would allow the cuff to adhereto itself may be used. Examples of such fasteners are adhesive-filledmicrocapsules or commercially available interlocking fasteners. Where a.pressuresensitive adhesive 30 is used, a protective liner maybe placedthereon until useor the portion of the film farthest from thebladderrnay be folded over the adhesive 30 as protection duringpackaging and merely unfolded prior to use exposing the adhesive.

When the cuff is to be used to take the blood pressure of a patient, thecuff is unfolded as shown .in FIGS. 2 and 3 and the adhesive area 30 isexposed. An audiopickup transducer 12 is inserted into the two slits(not shown) in the fabric layer 36 which is opposite the stem '14inserted during manufacture, and which area also comprises the bladder31. The bladder, with the fabric surface carrying the pickup devicewhich is to be placed against the skin, is then placed on the appendage26 where the blood pressure will be taken and the remainder of the cuffis wrapped over the bladder portion 31 and convolutely around theappendage and itself until the end of the cuff contacts the adhesivearea 30'. The cuff is thus adhered to itself and held on the appendageas illustrated in FIG. 1.

The stethoscope 1 8 may then be attached to the au die-pickup transducerand the readout device 22 and the pressure bulb is attached tothe stem;1 4 by meansof a single tube 20-. These attachments may also be madeprior to putting the cuff on the appendage. The blood pressuremeasurement is; then: taken inthe normal manner. I

The dimensions of the cuff are quite important. If the pad istoo"narrow, a greatdeal of pressure is-r'equiired to constrict thebloodvessels'underneath the skin. If too wide, thepressure isdistributed" over a larger area and will not be sufficient to constrictthe vessels for proper blood pressure measurement. For normal adultuse,.the cuff is about 26 to incheslong and about 6 inches wide. Thesize may vary depending upon the size" and physical characteristics ofthe appendage around which the cuffi's to be wrapped. Forexample, bloodpressure cuffs prepared for use with children would be of a smaller sizethan the dimensions heretofore stated.

The preferred embodiment of the invention is illustrated in FIGS. 4through 6-, acne-piece, disposable blood pressure cuff may be preparedby using a; reinforced ornon-stretchable film layer over the entiresurface of the cuff. i

The cuff comprises a first layer of an' elongated, generally rectangularsheet of a pliable, thermoplastic polymer film a secondelongated,'generally rectangular reinforced sheet of thermoplasticpolymer film 62' overlying the first layer 60" and sealed thereto aboutits periphery at 58 t0? provide at least one inflatable pocket 64, thefirst layers60 being further bonded to a nontoxic, nonirritating, soft,porous, hypoallergenic, conformable, moisture vapor permeable material56 which may be made fromany of the materials having. the propertiesheretoforedescribed. The latter material has slits-65 and 66-therein tohold a: picliup transducer and a stem- 52 is merelyinsertedthroughasmall opening 54 in the second layer andinto' thebladdenthe stem being held by a friction fit in the film or may besealed between the film layers. The stethoscope and pickup device may beattached as before. A pressure-sensitive adhesive tape 48 having aprotective liner 50 thereon is used to anchor the cuff to itself whenwrapped around an appendage. As illustrated, one bladder 64 is formedbetween the film layers 60 and 62. There may, however, be more than onebladder formed as in the cuff heretofore described. In the illustration,the second film layer 62 is somewhat thicker, thus reinforcing thatlayer so that the bladder will not rupture upon the introduction of airtherein. The reinforcement may be supplied, however, by using othermaterials in combination with the first polymer film, such as fibrousnylon cross hatching in the film. Various other methods of reinforcingthe outer layer of the cuff would be obvious to those skilled in theart.

The graphs illustrated in FIGS. 7 and 8 help to define the parameters ofthermoplastic films useful for making an acceptable blood pressure cuff,polyethylene being illustrated therein. In FIG. 7 the tensile force perinch of width necessary to elongate 20 percent is represented by number68 and the tensile force per inch of width necessary to exceed theelastic limit is represented by number 69, both being plotted as afunction of film thickness. The outer film 28 must have a minimumtensile force of at least 10 pounds per inch of width and is representedby line 70. The inner film 29 must have a minimum tensile force of atleast pounds per inch of width and is represented by line 71. Theminimum acceptable film thickness for the outer and inner layers isrepresented by vertical lines from the intersection of theaforementioned limits and the lower of the two strength thicknesses (68and 69), 72 and 73 respectively. The point at which the vertical lines72 and 73 cross the abscissa represent the minimum acceptable thicknessnecessary to form an acceptable blood pressure cuff using a particularfilm.

As illustrated in FIG. 8, an acceptable maximum film thickness fora'desired film, compared with stiffness, may be determined withreference to line 75. Films having a stiffness greater than inches,measured as hereinbefore described, and represented by the upper limit74, are unacceptable. The vertical line from the intersection of thestiffness upper limit 74 and the plot 75 represent the thickest filmhaving the acceptable conformability and stiffness to provide anacceptable blood pressure cuff. Films having greater thickness result ina cuff which lacks the required conformability.

For example, according to the illustration using polyethylene, it isknown that the minimum tensile force required for the inner layer of thecuff is about 5, and the stiffness can be no greater than 10 no matterwhat material'is being used. Thus, with polyethylene, the inner filmmust be at least 0.004 inches thick to provide adequate'tensilestrength. Similarly, the outer layer must have a minimum tensile forceof 10 pounds per inch width no matter what material is used and it canconveniently be determined that the minimum thickness of the outer layermust be at least about 0.008 inch. Looking at FIG. 7, it will be seenthat a polyethylene film having a thickness of 0.004 inch and- 0.008inch falls below the stiffness limit of -l0-(number 74') and,-.thus, thethickness of 0.004 inch polyethylene film'for the inner layer and a0.008 inch thick polyethylene outer layer would be suitablefor'fabricating a blood pressure cuff according to the presentinvention.

Similar plots for different materials would define the minimum andmaximum thicknesses which could be used to form an integral, one-piece,disposableblood pressure cuff and would be within the skill of the'ar't. Since a tensile force for the outer layer must always be at least10 pounds per inch width and for-tile inner layer must be at least 5pounds per inch width, and the stiffness of each layer must be less thanl0"i iich'es, the preparation of similar graphs showing the"elasti'climit and 20 percent elongation point of the material will indicate theminimum required thickness of the film for the two layers. The stiffnessof the material can then be charted to show whether the minimum requiredthickness, based on tensile force, also falls below the maximumstiffness of 10 inches.

What is claimed is:

1. An inflatable, integral, one-piece, disposable blood pressure cuff,comprising:

a first inner layer of an elongated, generally rectangular sheet ofthermoplastic polymer film having a minimum tensile force of 5 poundsper inch of width and capable of withstanding an inflation pressure ofabout 300 mm. Hg without elongating more than 20 percent and having aRockwell hardness no greater than M; second, generally rectangular outerlayer of thermoplastic polymer film overlying at least a portion of saidfirst layer having a minimum tensile strength of 10 pounds per inch ofwidth, capable of withstanding an inflation pressure of 300 mm. Hgwithout elongating more than 20 percent and having a Rockwell hardnessno greater than M120, said first and second layers having a stiffnessfrom about, 50 to 250 mm. when measured using ASTM Federal Test MethodStandard No. 19], Method 5204, December 31, 1968, said layers beingsealed together about a perimeter to provide at least one inflatablepocket between said first and said second layers;

a third layer of a soft, porous, conformable, moisture vapor permeablematerial having a compressibility of from about 1/64 to about 3/16 inch,said third layer surfacing the back of said first layer for contact withthe skin;

means projecting from said second layer for enabling inflation anddeflation of said pocket; and

means to adhere said cuff to itself when convolutely wrapped around anappendage to hold said cuff thereon.

2. The one-piece, disposable blood pressure cuff of claim 1 wherein saidmeans for inflation and deflation is a hollow stem projecting from saidsecond layer for inflation and deflation of said pocket.

3. The one-piece, disposable blood pressure cuff of claim 1 additionallycomprising means to hold an audio-pickup transducer onto said thirdlayer.

4. The one-piece, disposable blood pressure cuff of claim 1 wherein saidthermoplastic polymer film is polyethylene.

5. The one-piece, disposable blood pressure cuff of claim 1 wherein saidvapor permeable material is a fab- 6. The one-piece, disposable bloodpressure cuff of claim I wherein said vapor permeable material isreticulated foam having a density no greater than 10 pounds per cubicfoot.

7. The one-piece, disposable blood pressure cuff of claim 5 wherein saidfabric is a nonwoven web.

ASTM FederalTest Method Standard No. 191,

Method 5204, December 31, 1968, said layers being sealed together abouta perimeter to provide 8. An inflatable, integral, one-piece, disposableblood pressure cuff, comprising:

a first inner layer of an elongated, generally rectangular sheet of apliable, thermoplastic polymer film having a minimum tensile strength ofpounds per inch of width capable of withstanding an inflation pressureof 300 mm. Hg without elongating more than 20 percent and having aRockwell hardness no greater than M120;

a second layer of an elongated, generally rectangular outer layer of apliable, thermoplastic polymer film overlying said first layer andhaving a minimum tensile strength of 10 pounds per inch of width,capable of withstanding an inflation pressure of 300 mm. Hg withoutelongating more'than percent and having a Rockwell hardness no greaterthan M120, said first and second layers having a stiffness from about 50to 250 mm. when measured using polyethylene.

immcn s'lAfiEs PATENT uwuz'rz' 3 CERTIFICATE OF CORRECTION Inventor(s)J:'!g! H, HQyI W-. 4. -4-

ifimi 1: .u error appears in the above-identified patent It 1.; c6. andthat said Letters i'uterit are hereby corrouted as shown below:

Col. 5, line; 13, "construct" should read "gbnstriet".

Col. 5, line 33 would read "3/16" instead or "5/16".

Signed and sealed this 9th da of April 1.974.

(SEAL) Attest I G MARSHALL DANN EDWARD ELFLETCHEILJR.

Commissioner of Patents Attesting Officer

1. An inflatable, integral, one-piece, disposable blood pressure cuff,comprising: a first inner layer of an elongated, generally rectangularsheet of thermoplastic polymer film having a minimum tensile force of 5pounds per inch of width and capable of withstanding an inflationpressure of about 300 mm. Hg without elongating more than 20 percent andhaving a Rockwell hardness no greater than M120; a second, generallyrectangular outer layer of thermoplastic polymer film overlying at leasta portion of said first layer having a minimum tensile strength of 10pounds per inch of widTh, capable of withstanding an inflation pressureof 300 mm. Hg without elongating more than 20 percent and having aRockwell hardness no greater than M120, said first and second layershaving a stiffness from about 50 to 250 mm. when measured using ASTMFederal Test Method Standard No. 191, Method 5204, December 31, 1968,said layers being sealed together about a perimeter to provide at leastone inflatable pocket between said first and said second layers; a thirdlayer of a soft, porous, conformable, moisture vapor permeable materialhaving a compressibility of from about 1/64 to about 3/16 inch, saidthird layer surfacing the back of said first layer for contact with theskin; means projecting from said second layer for enabling inflation anddeflation of said pocket; and means to adhere said cuff to itself whenconvolutely wrapped around an appendage to hold said cuff thereon. 2.The one-piece, disposable blood pressure cuff of claim 1 wherein saidmeans for inflation and deflation is a hollow stem projecting from saidsecond layer for inflation and deflation of said pocket.
 3. Theone-piece, disposable blood pressure cuff of claim 1 additionallycomprising means to hold an audio-pickup transducer onto said thirdlayer.
 4. The one-piece, disposable blood pressure cuff of claim 1wherein said thermoplastic polymer film is polyethylene.
 5. Theone-piece, disposable blood pressure cuff of claim 1 wherein said vaporpermeable material is a fabric.
 6. The one-piece, disposable bloodpressure cuff of claim 1 wherein said vapor permeable material isreticulated foam having a density no greater than 10 pounds per cubicfoot.
 7. The one-piece, disposable blood pressure cuff of claim 5wherein said fabric is a nonwoven web.
 8. An inflatable, integral,one-piece, disposable blood pressure cuff, comprising: a first innerlayer of an elongated, generally rectangular sheet of a pliable,thermoplastic polymer film having a minimum tensile strength of 5 poundsper inch of width capable of withstanding an inflation pressure of 300mm. Hg without elongating more than 20 percent and having a Rockwellhardness no greater than M120; a second layer of an elongated, generallyrectangular outer layer of a pliable, thermoplastic polymer filmoverlying said first layer and having a minimum tensile strength of 10pounds per inch of width, capable of withstanding an inflation pressureof 300 mm. Hg without elongating more than 20 percent and having aRockwell hardness no greater than M120, said first and second layershaving a stiffness from about 50 to 250 mm. when measured using ASTMFederal Test Method Standard No. 191, Method 5204, December 31, 1968,said layers being sealed together about a perimeter to provide aninflatable pocket between said first and said second layers; a thirdlayer of a soft, porous, conformable moisture vapor permeable materialhaving a compressibility of from about 1/64 to 3/16 inch, said thirdlayer surfacing the back of said first layer for contact with the skin;means projecting from said second layer for enabling inflation anddeflation of said pocket; and adhesive means to attach one end of saidcuff to a remaining portion thereof to hold said cuff securely to anappendage.
 9. The cuff of claim 8 wherein said polymer film ispolyethylene.